GEARS (3D Motion Capture) Instructional Content

[boogielicious]

8 hours ago, Ty_Webb said:

One thing I would add to this by the way. A few driving ranges have mirrors behind the hitting bays that I've seen. I quite like them, but it's worth noting that because your eyes are not at hand height at address (one would hope at any rate), you're effectively looking at yourself from the high right angle, so if you're trying to have the club work up along the shaft line on your backswing, you'll be exaggerating it if you follow that line in the mirror (exaggerating assuming you're too far inside to start with)

That is what great about MirrorVision. I just look at the iPad at the different positions and I can see how it looks from the proper camera angle.

[ChetlovesMer]

18 hours ago, iacas said:

What do you think of this video?

Not blowing smoke.
That's a great video.

 

[GolfLug]

12 hours ago, iacas said:

No excuses, V! 😄

Nah, no excuses for sure... just wiser today than yesterday. 

[nevets88]

Hey, I just noticed AMG did a similar video on Gears with the viewing angles.

[iacas]

2 hours ago, nevets88 said:

Hey, I just noticed AMG did a similar video on Gears with the viewing angles.

Yeah it’s a few years old I think.

[Warlock]

On 12/15/2021 at 9:42 PM, GolfLug said:

Hmm.. no idea. But motion is still a series of static images. Higher the frequency, smaller the incremental unit of motion measured. All similar systems verification works the same way in principle - known size, rate of motion and mapping. I could be wrong there can't be any serious IP in that.

The 'money' is in the program that stiches the images together from all cameras to produce the resulting output. The data output is staggering especially rates of individual motion and relative movements IMO.

I remember something about  'phantom cameras' being used to check their computer generated images.

[iacas]

A few topics:

[nevets88]

So AMM just posted this and it basically says what's mentioned in the camera angle video above and recommends similar optimal camera placement.

 

[Warlock]

I wonder if GEARS has the capability to check the below:

1. How the tour pros PA2 angle is released in the downswing. Basically, a graph showing rate of change of the angle between shaft and lead forearm. 

For example, when looking at these kinematic sequence graphs, Rory's lead arm seems to have a greater angular velocity than the club (ie. the blue graph moves temporarily above the brown line). Same happens for Ricky Fowler, Ernie Els, Grant Waite and JB Holmes. 

Does this mean that the angle between the lead arm and club shaft is actually decreasing in the early downswing for the golfers I've just mentioned?

 

 

 2. For tour pros, does an extension of their club shaft trace a 'swing plane line' as demonstrated by Martin Hall's old you-tube video?

 

 

For example, Dr Kwon mentions that tour pros shafts swing on a functional swing plane (FSP) between MD (mid-downswing) and ZC (zero wrist-cock) in the image below which also traces the FSP plane base line.  He shows how the shaft deviates off that FSP in the downswing but there isn't any indication whether an extension of the shaft still continues to trace that FSP plane base line.

TGM proponents would define that tracing of the swing plane line throughout the downswing as swinging 'On Plane'. 

 

 

Edited July 20, 2022 by Warlock

[iacas]

8 hours ago, Warlock said:

1. How the tour pros PA2 angle is released in the downswing. Basically, a graph showing rate of change of the angle between shaft and lead forearm.

Yes.

8 hours ago, Warlock said:

Does this mean that the angle between the lead arm and club shaft is actually decreasing in the early downswing for the golfers I've just mentioned?

That's pretty common. Trail elbow and lead arm adduction also change a little bit then.

8 hours ago, Warlock said:

2. For tour pros, does an extension of their club shaft trace a 'swing plane line' as demonstrated by Martin Hall's old you-tube video?

Depends on a few things, including how strictly you're defining the "plane line" and when in the swing you're talking about.

On the downswing, Tour players tend to shift this line a lot less than most amateurs.

8 hours ago, Warlock said:

For example, Dr Kwon mentions that tour pros shafts swing on a functional swing plane (FSP) between MD (mid-downswing) and ZC (zero wrist-cock) in the image below which also traces the FSP plane base line.  He shows how the shaft deviates off that FSP in the downswing but there isn't any indication whether an extension of the shaft still continues to trace that FSP plane base line.

But as you can see, it doesn't deviate much. There are ams that are too shallow then too steep, then still try to find a way to hit the ball.

But then there are also pros like Matt Wolff, too.

[Warlock]

I was looking at HackMotion graphs of DJ on their website and wondering whether GEARS matches (approximately) the figures as per below?

Radial deviation of only 4  degrees at the top of the backswing seems  a bit on the low side even though its more difficult to do this when your wrist is bowed.

The increased bowing of the wrist just before impact also looks a bit strange and wondering how he is able to physically do that?

Edited July 22, 2022 by Warlock

[iacas]

3 minutes ago, Warlock said:

I was looking at HackMotion graphs of DJ on their website and wondering whether GEARS matches (approximately) the figures as per below?

Which specifically? And why…? HackMotion specifically and only measures the wrist.

3 minutes ago, Warlock said:

The increased bowing of the wrist just before impact also looks a bit strange and wondering how he is able to physically do that?

Specifically what? The green line? It could be extending because the handle goes while the clubhead slows as it hits the ball. Or it's just the last little roll that adds a little flexion.

[Warlock]

12 hours ago, iacas said:

Which specifically? And why…? HackMotion specifically and only measures the wrist.

Specifically what? The green line? It could be extending because the handle goes while the clubhead slows as it hits the ball. Or it's just the last little roll that adds a little flexion.

His radial deviation at P4 seems to look greater than 5 degrees in this sky sports video (or is this due to parallax)? Does GEARS also measure the same figure?

 

 

"Specifically what? The green line? It could be extending because the handle goes while the clubhead slows as it hits the ball. Or it's just the last little roll that adds a little flexion."

 

Not sure I understand what you meant above. What confused me is the flexion-extension graph showing increased flexion happening just before impact. Look at graph below where it shows increased flexion from -10 to  -21  degrees.  How can his lead wrist flex more when the pull force on his hands can be very high approaching impact?

 

I just wanted to know whether GEARS superior working frequency (is it 450 Hz?) corroborates similar wrist measurements as shown in HackMotion (which I think only operates at 100 Hz).

 

 

Edited July 22, 2022 by Warlock

[Warlock]

2 hours ago, Warlock said:

His radial deviation at P4 seems to look greater than 5 degrees in this sky sports video (or is this due to parallax)? Does GEARS also measure the same figure?

 

 

"Specifically what? The green line? It could be extending because the handle goes while the clubhead slows as it hits the ball. Or it's just the last little roll that adds a little flexion."

 

Not sure I understand what you meant above. What confused me is the flexion-extension graph showing increased flexion happening just before impact. Look at graph below where it shows increased flexion from -10 to  -21  degrees.  How can his lead wrist flex more when the pull force on his hands can be very high approaching impact?

 

I just wanted to know whether GEARS superior working frequency (is it 450 Hz?) corroborates similar wrist measurements as shown in HackMotion (which I think only operates at 100 Hz).

 

 

I've just found another HackMotion graph for DJ driver swing on one of Scott Cowx more recent you tube videos and it looks slightly different.

I think the top one must be out of phase because that increased flexion happens before impact whereas in the one below it happens after impact.

 

 

 

[iacas]

9 hours ago, Warlock said:

His radial deviation at P4 seems to look greater than 5 degrees in this sky sports video (or is this due to parallax)? Does GEARS also measure the same figure?

5° from when?

That video has him about 138.19° to 145.4°, so… a little over 7°.

9 hours ago, Warlock said:

Not sure I understand what you meant above. What confused me is the flexion-extension graph showing increased flexion happening just before impact.

I don't think that actually happens.

9 hours ago, Warlock said:

 

I think there's very little chance his wrist is extending fast from 1.8 to 1.95, flexes from 1.95 to 2.05, and then immediately changes direction again to extend from there on out.

I'd wager a lot of money it's a lack of precision or some other sort of mechanical issue with the HackMotion, not what DJ is actually doing. Not because HM is poor or anything, but just because of how it measures, the precision possible for a $700 device, etc.

Almost no chance that it goes from -10 to -21 like that. Not starting before impact. Move the impact line 0.05 seconds to the left and maybe it'd work. And even then, I'm still not sure the wrist actually does that, but I could see the "jolt" causing the HackMotion to read it that way.

Stuff is happening fast at that point in the swing.

7 hours ago, jshots said:

 

Would it be possible with gears to compare feet angle at address to face to path at impact of some better ball strikers?

Yes.

7 hours ago, jshots said:

I've had a theory that in the quest to be a more optimal ball striker, you should play with a slightly open stance.

Why?

7 hours ago, jshots said:

If you set up with feet on train tracks, a square face, and hit down on the ball, that would require that your rotate your club face more closed at impact relative to where it started otherwise you would have an open face and hit everything to the right.

Why?

7 hours ago, Warlock said:

I think the top one must be out of phase because that increased flexion happens before impact whereas in the one below it happens after impact.

Yup.